1. Technical Field
The present invention relates to a production system general-purpose cell and a production system having a line layout using the general-purpose cell.
2. Related Art
Regarding compact electrical products, electronic products, and the like, small batches of a variety of products have increasingly been produced and product cycles have increasingly been reduced in recent years.
Production lines producing the electrical products, electronic products, and the like tend to involve frequent rearrangement of line layouts in accordance with products to be produced.
Since it takes much time and cost to change such production lines in a changeover from production of one product to production of another product, cell production by human hands is used in many cases.
However, automatization of production lines is desired even in such cases from the viewpoints of product quality and production stability.
To address this issue, there has been proposed a system such as that disclosed in Japanese Patent No. 3336068, a first related art example.
In this system, a production system together with a conveyor that transports a workpiece placed on a pallet, which is a holding medium for a workpiece, is configured as assembling cells, as aimed at reduction of losses in time and costs relevant to a line configuration.
That is, this system allows selective supply of parts from a plurality of parts supply devices, which are separately disposed, to each divided cell and causes the cell itself to have a function of machining workpieces suitably for a variety of products to thereby reduce losses in time and costs and promote automatization.
There has been proposed another system such as that disclosed in Japanese Patent No. 3673117, a second related art example.
In this system, a robot placed on a base of a cell (robot unit) that is adjacent to a cell in question with a working bench interposed therebetween is provided, and an assembling tool of the robot as well as parts of a workpiece are transported to the cell in question so that the robot itself attaches and detaches the assembling tool and performs machining operations for the workpiece.
Providing a transportation means that carries in an assembling tool required for of each cell together with parts of a workpiece and carries out the assembling tool after use together with the workpiece machined by the robot, as mentioned just above, further promotes the aforementioned automatization.
On the other hand, there has been still another system such as that disclosed in JP-A-2006-43844, a third related art example, in view of a disadvantage of providing the foregoing robot on the base.
In this system, robots are supported in a state of ceiling-hung by using supporting members provided separately from assembling work benches, and parts supply units that supply parts to movable ranges of the robots are disposed facing the robots.
Supporting the robots in a state of ceiling-hung as mentioned just above allows space on the assembling work benches (bases) to be widely secured, and in turn the degree of freedom relevant to assembling operations on the assembling work benches to be maintained higher.
As described above, various systems have been proposed so as to reduce losses in time and costs required for changes of a line configuration and further promote automatization.
However, from the viewpoints of general versatility as the foregoing cell or the degree of freedom in a line layout, there is still room for improvement.
For example, in the case of a cell or a system described in the first related art example, pallets for holding the aforementioned workpieces need to be prepared by type for various types of workpieces (products) that are production objects.
In implementing the system, a large amount of pallets are therefore needed.
Time and costs required for the design and manufacture cannot be ignored.
In addition, this system is one of transporting the pallets by a conveyor.
Therefore, the system involves a disadvantage in that the production quantity and production capacity of a line are limited by the transportation capacity of the conveyor itself.
In the case of a system described in the second related art example, the foregoing conveyor and the like are unnecessary.
However, the system has a structure in which a robot is placed on a base constituting a cell.
Therefore, restrictions on the operation area required for processing of a workpiece including attachment and detachment of an assembling tool by a robot itself and further restrictions on the size of a tray transported by the foregoing transportation means cannot be ignored.
If a large operation area and a large tray size are secured, upsizing of the entire production system including a cell cannot be avoided.
In a system described in the third related art example, although space on the assembling work benches can be widely secured, the parts supply units are configured to face the assembling work benches.
The degree of freedom of a line layout is limited of itself.
After all, it is difficult to reduce losses in time and costs required for changes in a line configuration.